The Range Rover and the Porsche 911 are pretty much the same car. Or so I’m thinking as I take a brand new, totally redesigned Range Rover HSE up a cracked rock ledge, scrambling atop a high desert mesa.

One’s provenance is British, the other German, and they look utterly unalike. Yet I can think of no other two modern vehicles that have gone beyond their histories and eccentricities to define contemporary luxury.

You don’t need a Range Rover or 911. But both are incredibly easy to want.

Like the Porsche, the Range Rover has a long history behind it. The company Land Rover got its start after World War II, and the first Range Rover model was released in 1970. (The Range Rover came to the U.S. in the late 1980s.)

The 2013 model year is its fourth major redesign. And like the 911, those redesigns have brought deep wells of technology, cushy seats and fancy navigation screens, but the overall shape of the exterior is roughly the same. Desert Drive

Both the Range Rover and the Carrera have a breadth of capability that far exceeds what most owners will ever experience. A typical excursion may only take you to dinner, theater and back, but part of that deep desirability springs from the knowledge that you could run the Range Rover across the Sahara or the 911 on the famous Nurburgring racetrack.

The subtext: I’m not just some suburban soccer dad. I’m ready to rumble, and I’ve got the car keys to prove it. The new Range Rover starts as a base model ($83,500), a better equipped HSE model ($88,500), and the Supercharged version ($99,950). China has become the company’s biggest market, and the $130,950 Autobiography is aimed at those customers, with an extra fancy interior and an emphasis on rear- seat comfort.

I’m torn over the new design. This generation has undergone significant changes, not all for the better. The edges on the front and rear have been significantly softened, the cant of the windshield less upright. Its quasi-military stance has been de- boxed.

Body Contours

Those changes are doubtlessly smart, improving aerodynamics and speaking to a consumer more interested in luxury than utility. But I absolutely hate the new headlights and taillights, which now wrap around to the sides. It looks like the Ford (F) Flex crossover. The roof is also lower, affecting the overall proportions.

Once inside, however, I forget those quibbles. The interior is just too good. It’s masculine and simple, with a bare minimum of fussy buttons. Changing most settings, like turning up the air, is dead simple. It’s the opposite approach to the Porsche Cayenne SUV, which has so many controls it looks like a jet cockpit.

The Range Rover’s leather is super supple and the headrests are so cushy I’d like to take them to bed.

Like the 911, the Range Rover has long called out to me despite its obvious impracticalities. The last one weighed some 5,700 pounds, with an around-town gas mileage of 12 miles per gallon.

Shedding Pounds

Those inefficiencies speak to the greatest trick of the new model: It’s made of aluminum. Everything from the suspension to the body panels is made of the light stuff, which is a first for a SUV. This saves 700 pounds, enabling the Range Rover to drive better on every surface, whether it’s the highway, a byway or off-road.

The 5.0-liter V-8 engine is a carryover from the previous model, with 375 horsepower and 375 pound-feet of torque. The acceleration on the outgoing HSE was languorous. It certainly made the Supercharged version (510 hp; 461 lb-ft) a lot more attractive.

This time the HSE’s power feels totally appropriate. The new eight-speed ZF transmission snaps through gears in the background, providing the right oomph at the right time. Gas mileage, always an Achilles’ heel, is slightly more virtuous on the new HSE model, getting 14 mpg city and 20 highway.

I’m one of the few maniacs who believe that Range Rovers should be taken off-road, and was worried that the emphasis on greater luxury would translate to lesser 4X4 performance. A good sign: It has better underbody clearance than previously.

Dirt Roads

The Range’s continued off-road prowess was proven in the broken landscape of southern Utah -- the kind of country which looks like Wile E. Coyote (TWX) might drop from a cliff at any moment. Over a half day driving off piste, the terrain varied from snow- slicked dirt roads, to boulder screes and undulations of naked, slick rock.

Using the 4X4’s low range and a light throttle, I drove a Supercharged model through truly hellacious territory with absolutely no drama. The over-sized tires crabbed easily over boulders and the air suspension ably soaked up the uneven ground.

The worst thing that happened to the vehicle? I rolled down the windows and splashed headlong into a few mud puddles, splattering the white leather with goop. I almost felt guilty. Almost.